1. Field of the Invention
The present invention relates generally to the field of heating and cooking apparatus and more particularly to disposable, canned fuel heating and cooking devices.
2. Background Discussion
The use of disposable, self-contained canisters or containers of heating and cooking fuel is widely known for camping and in emergency situations where utility sources of gas and electricity are out of service, for example, in the event of earthquakes, hurricanes and other disasters. One common type of such cans of heating and cooking fuel is STERNO, which is sometimes referred to as "canned heat." STERNO cans are similar in appearance and construction to half-pint paint cans and have the same type of removable and replaceable covers as paint cans. The fuel contained in the cans is a gel-type fuel. In use, the cover is removed and the fuel is ignited to provide a flame. A cooking utensil is placed on top of the can for cooking purposes. Such cans of heating and cooking fluid are relatively inexpensive, are readily stored for protracted periods of time and are disposable when the contained fuel is completely consumed.
Other types of canned fuel heating and cooking devices are also known. For example, U.S. Pat. No. 4,624,633 to David Bandel discloses a high percentage glycol fuel and a fuel canister used to contain the fuel. A wick protruding from the top of the canister provides a flame for heating and cooking. U.S. Pat. No. 4,611,986 to J. Alan Mentor discloses a particular configuration for use with a canister of fuel, the wick, which extends upwardly from the top of the canister is split, flame control being provided by separation of the two wick sections.
As another example, U.S. Pat. No. 4,604,053 to Rudolpho de la Rosa discloses another fuel-containing canister device in which an elongated wick having two separate end regions that extend into the fuel contained in the canister. A central region of the wick is exposed for burning through an aperture in the top of the canister. Further, U.S. Pat. No. 3,888,620 to Harry J. Devon discloses a heat and cooking source that employs a solid wax contained in the burner canister. When exposed regions of a wick are lit, metal wires conduct heat into the body of wax in the canister, thereby melting it so that the fuel becomes a liquid which is readily burned to provide more heat than is provided, for example, by a wax candle.
U.S. Pat. No. 4,850,858 to Robert J. Blankenship et al discloses another type of canned heat device in which a disc-shaped plastic foam burner pad is disposed at the top of a liquid fuel canister, a wick extending between the pad and fuel in the container wicks fuel into the foam pad. A central region of the plastic foam pad is exposed through an opening in the top of the canister and is lit to provide a heating and cooking flame.
U.S. Pat. Nos. 960,064 to Samuel Bergstein and No. 3,262,290 to Georg Huber disclose other types of liquid fuel burners.
One disadvantage of such known heating and cooking devices is that the control of the amount of flame and heating area is difficult to vary according to particular user needs. For example, the more simple devices provide no burning control whatsoever. Once lit and burning, the fuel provides a generally uniform heat output until the fuel is entirely consumed. Depending upon the use, such lack of control of heat output is undesirable and the result may be burned food, excessive heat (for example, in a small tent) and very rapid consumption of fuel. In other devices, the extent of burning control is not adequate for many uses where heat control, such as is commonly provided by a conventional gas or electric stove, is needed.
For these and other reasons, the present inventor has invented an improved, flame adjustable fuel container apparatus in which the amount of burning and heat provided by combustion of the contained fuel is adjustable over a wide range between an "off" condition, to a full "open" condition.